Delavan Lake vs Lake Beulah
Water quality, depth, fish species, and recreation comparison.
Lake Beulah has a higher water quality grade (A, Excellent) than Delavan Lake (B, Good). Both are in Walworth County, Wisconsin.
Both Delavan Lake and Lake Beulah sit in Wisconsin. A same-state comparison strips out the state-level water-quality regime as a variable: any grade differences here are about the lakes themselves, not the agencies grading them. These two are within a letter of each other on the rubric — Delavan Lake (B) versus Lake Beulah (A). The deciding factors for a recreational visitor are likely physical (depth, access, fish species) rather than water-quality differences.
With grades this close, the choice between the two lakes turns on non-water-quality factors: depth, fish species, public access, distance from home. The per-lake pages below cover all of those.
Delavan Lake
No clarity data.
Lake Beulah
Good clarity, visible to about 10 ft.
Side-by-Side Metrics
| Metric | Delavan Lake | Lake Beulah |
|---|---|---|
| Overall Grade | B (Good) | A (Excellent) |
| Water Clarity | No data | 10 ft |
| Phosphorus | 25.9 µg/L | 13.4 µg/L |
| Chlorophyll-a (Algae) | No data | 2.5 µg/L |
| Maximum Depth | 52 ft | 58 ft |
| Surface Area | 1,906 acres | 812 acres |
| Public Access | Yes | Yes |
| Fish Species | 6 | 3 |
| Trophic State | eutrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Lake Beulah wins on overall water quality with a Grade A versus Delavan Lake's Grade B. For more fish-species variety, Delavan Lake edges ahead with 6 documented species.
Source: EPA National Aquatic Resource Surveys, 2026.